1. Field of the Invention
This invention relates to a pneumatic radial tire, more particularly to a pneumatic radial tire which can improve cornering performance at high speed running and riding comfortability as well.
2. Description of the Prior Art
Recently, improvement of road networks, high power of cars and enhancement of performance have tended to increase car speed more and more. While the running performance at a high speed on straight roads and highways is as a matter of course satisfactory, the cornering performance is on the other hand a problem in such cars. That is, there is a need for performance which guarantees cornering at a high speed with safety. In general, as a measure for improvement of cornering performance, strengthening the rigidity of the region around bead base portions by providing reinforcing layers extending from this region to an area in a sidewall portion having maximum width has been suggested.
By adopting such reinforcing layers, though the rigidity apparently increases, on the contrary disadvantages caused by weight, cost and further deterioration of the riding comfortability were found upon actual running of the car.
Having regard to the above, it is an object of this invention to provide a pneumatic radial tire which has improved riding comfortability and cornering performance without increasing the weight of the tire.